JP2005226493A - Engine supervising device of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine supervising device of a construction machine for correctly grasping condition of an engine, precisely predicting engine abnormality and correctly performing preventive maintenance by collecting data eliminated changes in operation condition of the engine as much as possible. <P>SOLUTION: The engine supervising device comprises an engine monitor section 21, a radio 26 connected to the engine monitor section and performing communication, an antenna 27 connected the radio 26 and an indicator 25. The engine monitor section 21 is connected to an electric lever control section 19 and to an engine control section 20. An operation signal inputted by a worker, e.g. a boom raising operation signal or the like, is inputted from the electric lever control section 19 and position information of a throttle dial 22 (a target rotation speed), a detection signal of an engine speed sensor 23 and a signal of an auto idling switch 24 are inputted from the engine control section 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a management device for construction machines such as a hydraulic excavator provided with an engine, and more particularly to an engine management device for a construction machine that performs preventive maintenance of the engine of a construction machine such as a large hydraulic excavator.

  Construction machines, particularly construction machines such as large hydraulic excavators, are used for debris excavation work at, for example, a large work site. The hydraulic excavator is generally continuously operated in order to improve productivity. For this reason, when an abnormality occurs in the engine, the operation of the hydraulic excavator must be stopped and repaired, but the engine repair often requires a long time, and the hydraulic excavator must be stopped for a long period of time. Things can happen. In this case, since the production work by the hydraulic excavator is interrupted, the operation of the production plan must be changed.

  Therefore, it is necessary to predict the abnormality of the engine in advance by detecting the state quantity of the engine and performing a health check. For example, Japanese Patent Application Laid-Open No. 2002-180862 relates to the performance of the drive device including the engine. By detecting multiple types of data (for example, fuel consumption, cooling water temperature, exhaust temperature) during operation, and centralizing these detection data together with reference values of various data, the current performance of the drive unit It has been proposed to express numerically.

JP 2002-180862 A

  In construction machines such as large hydraulic excavators, when the engine cylinder liner is worn, the engine output decreases, the engine load factor increases, and the thermal load increases, resulting in cylinder liner seizure and engine damage. is there. As described above, particularly in a construction machine such as a large hydraulic excavator that is continuously operated, if an abnormality occurs in the engine, the operation of the hydraulic excavator has to be stopped for a long period of time for repair. Because the production work due to is interrupted, the operation of the production plan must be changed.

  In the prior art described in Japanese Patent Application Laid-Open No. 2002-180862, a plurality of types of data related to the performance of the drive device including the engine are detected during the operation, and these detection data are unified, and the current performance of the drive device. The performance of the engine is evaluated by numerically expressing. However, in this prior art, the detection of the state quantity of the engine is performed periodically for a fixed time or constantly during operation. For this reason, the detected value of the state quantity includes a fluctuation component that depends on the operating state (working state) of the construction machine, and there is a problem that accurate diagnosis cannot be performed.

  That is, in a construction machine such as a hydraulic excavator, the load applied to the engine changes depending on the operation state (working state) of the construction machine, and the state quantity related to the engine changes greatly. For example, the engine load is large when the boom is raised, and the engine load is small when the boom is lowered. When the engine load is large, the amount of decrease in the engine speed and the amount of fuel consumption are increased, and the exhaust temperature and the like are higher than when the engine load is small.

  In the prior art described in Japanese Patent Laid-Open No. 2002-180862, detection of the engine state quantity is performed periodically for a fixed time or constantly during operation, regardless of such changes in the operating state. The detected state quantity includes a fluctuation amount due to a change in the driving state, and the numerical value of the current performance of the drive device obtained by the unification process also changes in accordance with the change in the driving state, so that an accurate diagnosis cannot be performed.

  It is an object of the present invention to accurately grasp the state of the engine by collecting data that eliminates as much variation as possible due to changes in the operating state of the construction machine, and to achieve accurate preventive maintenance of the engine. It is to provide an engine management device for construction machinery.

  (1) In order to achieve the above object, the present invention includes an engine, a variable displacement hydraulic pump driven by the engine, and a hydraulic actuator driven by pressure oil discharged from the hydraulic pump. In an engine management device for a construction machine, a rotational speed detection means for detecting the rotational speed of the engine and a load input detection that detects that a predetermined load is applied to the engine and outputs the detection result as a signal Means, a first processing means for taking in a detection value detected by the rotational speed detection means based on a detection signal of the load input detection means, and storing it as primary data of the engine rotational speed, and an engine in the first processing means The primary data of the rotational speed is aggregated, and the secondary data of the engine rotational speed at every predetermined time is created, and this is used as the engine related to the preventive maintenance of the engine. Shall and a second processing means for outputting as trend data down speed.

  As described above, the engine speed detection means, the load input detection means, and the first processing means are provided, and when it is detected that a predetermined load is input to the engine, the speed detection means is based on the detection result. Is detected and stored as primary data of the engine speed, it is possible to collect data that eliminates as much fluctuation as possible due to changes in the operating state of the construction machine, and the second processing means uses the engine speed. The primary data of the engine is aggregated, the secondary data of the engine speed per predetermined time is created, and this is output as trend data of the engine speed related to the preventive maintenance of the engine. Thus, accurate preventive maintenance of the engine can be achieved.

  (2) In the above (1), preferably, the load application detecting means is means for detecting whether or not a predetermined operation member driven by the hydraulic actuator has been subjected to a predetermined operation.

  Thereby, the load input detecting means can detect that a predetermined load is input to the engine.

  (3) In the above (2), preferably, the construction machine includes a front working machine having a boom, the predetermined working member is the boom, and the load input detecting means is configured to check whether the boom has been raised. It is a means for detecting whether or not.

  Thereby, the load input detecting means can detect that a predetermined load is input to the engine.

  (4) In the above (1), preferably, the first processing means takes in an engine speed after a predetermined time has elapsed after the predetermined load is applied as a detection value of the speed detection means. is there.

  As a result, it is possible to collect data excluding the fluctuation amount due to the transient change in the engine speed immediately after the load is applied, and it is possible to accurately grasp the state of the engine.

  (5) In the above (1), preferably, the first processing means takes in the lowest engine speed after the predetermined load is applied as a detection value of the speed detection means. .

  Thus, by always taking in the lowest engine speed after the load is applied, it is possible to collect data that excludes the fluctuation amount due to the change in the operating state, and it is possible to accurately grasp the state of the engine.

  (6) Further, in the above (1), preferably, the second processing means uses the trend data of the engine speed related to the overhaul implementation timing of the engine as the trend data of the engine speed related to the preventive maintenance of the engine. Means for creating, and display means for displaying the trend data of the engine speed and the determination reference value of the overhaul implementation timing of the engine.

  This makes it possible to accurately predict the engine overhaul time by looking at the display contents of the display means, making it possible to prepare in advance for overhaul and minimizing the impact of interruption of production work by construction machinery. Can do.

  (7) In the above (1), preferably, the second processing means creates trend data of engine speed related to engine abnormality as trend data of engine speed related to preventive maintenance of the engine. Means, and display means for displaying the trend data of the engine speed and the determination criterion value of the abnormality of the engine.

  As a result, it is possible to accurately predict engine abnormality such as damage to the piston ring due to impact, for example, by looking at the contents of the display means, and engine failure can be prevented in advance.

  (8) In the above (7), preferably, the second processing unit further includes an alarm unit that compares the trend data of the engine speed with the determination reference value of the abnormality of the engine and outputs an alarm. .

  Thereby, for example, engine abnormality such as damage to the piston ring due to impact can be reliably grasped, and engine breakage can be prevented in advance.

  According to the present invention, it is possible to accurately grasp the state of the engine and to perform accurate preventive maintenance of the engine.

  Further, according to the present invention, it is possible to accurately predict the overhaul implementation time of the engine, it is possible to prepare in advance for the overhaul, and the influence due to the interruption of the production work by the construction machine can be minimized.

  Furthermore, according to the present invention, it is possible to accurately predict engine abnormality such as damage to the piston ring due to impact, and prevent engine breakage.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a side view showing the entire structure of a large hydraulic excavator as an example of a construction machine to which the present invention is applied.

  In FIG. 1, reference numeral 1 denotes a large hydraulic excavator. The large hydraulic excavator 1 includes a lower traveling body 3, a revolving body 4 provided on an upper portion of the lower traveling body 3, and a swiveling body 4. An articulated front working machine 6 provided at the front center so as to be able to move up and down is provided. The lower traveling body 3 is provided with endless track crawlers (crawlers) 2 and 2 which are traveling means on both the left and right sides, and the left and right crawler belts 2 and 2 are operated by rotational driving of left and right traveling hydraulic motors 2a and 2a. It is supposed to be. The swivel body 4 includes a driver's cab 5 provided on the left side of the front part, and is driven to rotate with respect to the lower traveling body 3 by a turning hydraulic motor (not shown). The front work machine 6 includes a boom 7, an arm 8 that is rotatably provided at the tip of the boom 7, and a bucket 9 that is rotatably provided at the tip of the arm 8. The bucket 9 is rotated by a boom hydraulic cylinder 10, an arm hydraulic cylinder 11, and a bucket hydraulic cylinder 12, respectively.

  FIG. 2 is a diagram illustrating a configuration of an embodiment of the engine management device for a construction machine according to the present invention together with a hydraulic drive device for the construction machine.

  In FIG. 2, the hydraulic drive device of the large excavator 1 includes an engine 13, a main hydraulic pump 15, and the boom hydraulic cylinder 10. As hydraulic actuators of the large excavator 1, in addition to the boom hydraulic cylinder 10, the left and right traveling hydraulic motors 2a and 2a, the turning hydraulic motor (not shown), the arm hydraulic cylinder 11, and the bucket There are hydraulic cylinders 12 for example, which are omitted in FIG. The engine 13 includes an electronic control governor 14 that changes the fuel injection amount by a control signal. A main hydraulic pump 15 (hereinafter simply referred to as a hydraulic pump) is driven by an engine 13, and a boom hydraulic cylinder 10 (hereinafter simply referred to as a boom cylinder) is driven by pressure oil discharged from the hydraulic pump 15.

  The hydraulic drive device of the large excavator 1 includes a pilot pump 16, a control valve 17 that controls the flow rate of pressure oil supplied from the hydraulic pump 15 to the boom cylinder 10, and an electric for instructing the operation of the boom cylinder 10. A lever-type operation lever device 18 and an electric lever control unit 19 are provided. When the operation signal (electric signal) of the boom 7 is input from the operation lever device 18, the electric lever control unit 19 performs a predetermined calculation process on the operation signal, generates a drive signal (control signal), and performs electromagnetic proportional pressure reduction. Output to valves 17a and 17a. The electromagnetic proportional pressure reducing valves 17a and 17a reduce the primary pilot pressure output from the pilot pump 16 in accordance with the drive signal input from the electric lever control unit 19 to generate an operating pilot pressure. The operating pilot pressure is controlled by the control valve. 17 and the control valve 17 is switched. As a result, the operator can operate the operation lever device 18 to drive the boom 7.

  Further, the hydraulic drive device of the large excavator 1 includes a throttle dial 22 that instructs a target rotational speed of the engine 13, an engine rotational speed sensor 23 that detects the actual rotational speed of the engine 13, an auto idle switch 24, and engine control. Part 20. The engine control unit 20 inputs the position information (target speed) of the throttle dial 22 and the detection signal (actual speed) of the engine speed sensor 23 to calculate a necessary fuel injection amount, and electronically controls based on the calculated fuel injection amount. A control signal is output to the governor 14 to control the rotational speed of the engine 13 according to the target rotational speed. The auto idle switch 24 is a mode selection switch for operating the auto idle function, and the engine control unit 20 inputs the signal of the auto idle switch 24 and the operation signal of the operation lever device 18, and the auto idle switch 24 is turned on (automatic). The electronic control governor 14 is controlled so as to lower the engine 13 to the idle speed when the operator does not operate the operation lever device 18 for a certain period of time when the idle position is selected.

  The engine management apparatus according to the present embodiment is provided in a large-sized hydraulic excavator provided with the hydraulic drive apparatus as described above, and is connected to the engine monitor unit 21 and the engine monitor unit 21 to perform communication. And an antenna 27 connected to the radio device 26 and an indicator 25. The engine monitor unit 21 is connected to the electric lever control unit 19 and the engine control unit 20. The operation signal input by the operator, such as a boom raising operation signal, is input from the electric lever control unit 19. The position information (target speed) of the dial 22, the detection signal of the engine speed sensor 23, and the signal of the auto idle switch 24 are input. The engine monitor unit 21 performs predetermined processing based on the various types of signal information input above, and transmits engine speed information to a management office 28 (to be described later) via the wireless device 26 and the antenna 27, while also detecting engine abnormality. Is detected, the lamp of the indicator 25 is turned on to notify the operator of the abnormality of the engine 13.

  The engine management apparatus according to the present embodiment also includes a management office 28 installed outside the large excavator 1, and this management office 28 is connected to the calculation display device 29 and the calculation display device 29 for communication. And an antenna 31 that is connected to the wireless device 30 and provided in the outdoor part of the management office 28. The calculation display device 29 receives the engine speed information from the engine monitor unit 21 via the radio device 30 and the antenna 31, performs a predetermined process on this information, and displays it to the administrator. Based on this display, the manager predicts the time of overhauling the engine 13 and diagnoses the failure, and makes an input to inform the operator of the result. The calculation display device 29 transmits the input instruction to the engine monitor unit 21, and the engine monitor unit 21 receives the instruction and displays it on the display unit to notify the operator.

Here, the case where there is one large hydraulic excavator for the management office 28 has been described, but there may be a plurality of large hydraulic excavators, and other hydraulic working machines may coexist. Furthermore, by using the radios 26 and 30 as radios using hygiene, the management office 28 can be a maintenance center that centrally manages hydraulic work machines from around the world in one place.
FIG. 3 is a main flowchart of processing performed in the engine monitor unit 21 of the large excavator 1 of the present embodiment.

  In FIG. 3, it is first determined whether or not the engine 13 is in an activated state (S110). This determination is made, for example, based on whether or not the engine speed detected by the engine speed sensor 23 is above a predetermined level. If it is determined that the engine 13 is not activated, the determination process is repeated. On the other hand, if it is determined that the engine 13 is running, whether the auto idle switch 24 is OFF, whether the throttle position information from the throttle dial 22 is maximum, the electric lever control unit 19 raises the boom. It is determined whether an operation has been instructed (S120). If even one of these three determinations is denied, the determination process in step 120 is repeated without proceeding to the next process.

  Here, the purpose of performing the above three determinations is to detect a change in the rotational speed when a load is applied to the engine 13 when the engine target rotational speed is constant. That is, it is determined whether or not the auto idle switch 24 is OFF, and when it is ON, the process is not shifted to the next process, thereby excluding the case where the engine speed has decreased to the idle speed in the idle mode. Further, it is determined whether or not the throttle position information from the throttle dial 22 is maximum. Otherwise, the process does not proceed to the next process, thereby excluding when the engine 13 is at a speed other than the maximum speed. . Then, it is determined whether or not a boom raising operation has been instructed. When the boom raising operation is not performed, the process is not shifted to the next process, thereby excluding cases where different types of loads other than the boom raising operation are applied. Here, raising the boom is an operation with relatively little load fluctuation. Therefore, such three determinations make it possible to detect a change in the rotational speed when a predetermined load is applied to the engine 13 when the engine target rotational speed is constant (maximum).

  If all the above three determinations are affirmed, it is then determined whether or not a predetermined time, for example, 5 seconds has elapsed (S130), and when 5 seconds have elapsed, the actual engine speed detected by the engine speed sensor 23 is determined. Input from the engine control unit 20 and record it in the memory of the engine monitor unit 21 (S140). The purpose of determining whether or not the predetermined time has elapsed is to exclude the transient state of the engine speed change at the time of loading. Subsequently, an overhaul data creation process (S150) and an abnormality detection process (S160) are performed, and thereafter the processes of steps S120 to S160 are repeated.

Here, the change in the rotation speed of the engine 13 during the boom raising operation will be described with reference to FIG. FIG. 4 is a diagram showing a change in the actual engine speed when a boom raising operation is input from the non-operating state to the operation lever device with the auto idle switch OFF and the throttle dial being maximum, and then returned to the non-operating state. is there.
In FIG. 4, the vertical axis represents the engine speed, and the horizontal axis represents the elapsed time t. As described above, the engine 13 is provided with the electronic control governor 14, and the engine control unit 20 uses the position information (target speed) of the throttle dial 22 and the detection signal (actual speed) of the engine speed sensor 23. The fuel injection amount is calculated, and a control signal is input to the electronic control governor 14 based on the calculated fuel injection amount to control the engine 13 to the target rotational speed. In this case, when the engine 13 is in a no-load state, the engine speed is a high idle speed higher than the target speed. Here, when a boom raising operation is input to the operation lever device 18 (t1), a phenomenon of lag-down in which the rotation speed of the engine 13 falls for a moment occurs (t1 to t2). This is because when the engine 13 is in a no-load state, the rotational speed of the engine 13 is in a high idle state as described above, and the amount of fuel supplied to the engine 13 in this state is small, whereas the engine 13 This is because the electronic control governor 14 tries to supply a large amount of fuel when a load is applied, but the control is delayed in response, so that the amount of fuel supply becomes transiently insufficient. Then, as the fuel supply increases, the engine speed increases and reaches the rated speed (target speed) (t2 to t3). Thereafter, the rated rotational speed is maintained until the operation lever device 18 is returned to the neutral position (t3 to t5), and then the engine rotational speed returns to high idle.

  When the operation is performed from the no-load state as described above, the engine speed decreases greatly in a transient manner. Therefore, in the present embodiment, in steps S130 and S140 of FIG. 3, the engine speed is increased after a predetermined time (for example, 5 seconds). The number is measured, and the stable engine speed at the rated speed is measured.

  In this embodiment, the boom raising operation is taken as an example of the type of the input load, but this is because the boom raising has the least variation in the magnitude of the load. However, if there is little variation in the magnitude of the load, a load other than the boom raising may be detected. Further, the rated rotational speed is measured as the measurement of the engine rotational speed. However, the rotational speed at this time may be measured by taking the timing of the time t2 when the engine rotational speed has dropped to the maximum.

FIG. 5 is a flowchart showing details of the overhaul data creation processing S150 of FIG.
In FIG. 5, it is first determined whether one day has passed since the last overhaul data creation process (S210). If one day has not elapsed, the process is terminated, and the process proceeds to the abnormality detection process S160 in FIG. If one day has elapsed, an average value D1 (hereinafter referred to as average value D1) of the engine revolutions measured and recorded in step S140 of FIG. 3 is calculated (S220), and the calculated average value D1 is managed. Processing to transmit to the calculation display device 29 at the place 28 is performed (S230).

FIG. 6 is a flowchart showing details of the abnormality detection process S160 of FIG.
In FIG. 6, it is first determined whether or not 30 minutes have passed since the previous abnormality detection process (S310). If 30 minutes have not elapsed, the process exits and returns to the main flowchart of FIG. 3, and the process of FIG. 3 is repeated from step S120. When 30 minutes have elapsed, an average value D2 (hereinafter referred to as average value D2) of 30 minutes of the engine speed is calculated (S320), and the calculated average value D2 is recorded in the memory of the engine monitor unit 21. The data is transmitted to the calculation display device 29 (S330). Next, the average value D2 recorded in the engine monitor unit 21 is compared with the warning generation reference rotation speed N2. If the average value D2 is not lower than the warning generation reference rotation speed N2, the process is exited, and the main flowchart of FIG. Returning to step S120, the process of FIG. 3 is repeated from step S120.

  Here, the warning generation reference rotational speed N2 is a reference value for determining an abnormality of the engine 13, and when the average value D2 is lower than the warning generation reference rotational speed N2, some action is required immediately. It is determined that an abnormality has occurred. Here, the abnormality of the engine 13 is, for example, a sudden damage to a piston ring, an intake / exhaust valve, or the like. A rotational speed lower than the number N1 is set.

  If the average value D2 is lower than the warning occurrence reference rotational speed N2 in the above determination, a warning is output (S350). There are two types of warning outputs, one is an indicator output that lights the indicator 25 and informs the operator, and the other is a warning transmission that is transmitted to the calculation display device 29 of the management office 28 and communicated to the administrator. . As a result, the operator knows the abnormality of the engine 13 and can take measures such as stopping the engine 13 as soon as possible. The management office 28 can also grasp the situation and perform appropriate processing. After the warning is output, the process returns to the main flowchart of FIG. 3, and the process of FIG. 3 is repeated from step S120.

FIG. 7 is a flowchart showing the processing of the calculation display device 29 installed in the management office 28.
In FIG. 7, it is determined whether or not the average value D1 has been received from the hydraulic excavator 1 (S410). If it has not been received, the process proceeds to step S460. (S420). Subsequently, it is determined whether or not 30 days have passed since the date when the previous average value D3 was calculated (S430). If 30 days have not passed, the process proceeds to step S460, and if 30 days have passed, the calculation display device. An average value D3 for 30 days (hereinafter referred to as average value D3) of the average value D1 recorded in the memory 29 is calculated (S440). Then, the average value D3 is recorded in the memory of the calculation display device 29, and the data of the display content 1 displayed on the calculation display device 29 is changed (S450).

  Subsequently, it is determined whether or not the average value D2 is received from the hydraulic excavator 1 (S460). If it has not been received, the process proceeds to step S480. If it has been received, the average value D2 is recorded in the memory of the calculation display device 29, and the data of the display content 2 displayed on the calculation display device 29 is changed ( S470).

  Subsequently, either display content 1 or display content 2 is displayed on the screen 29a of the calculation display device 29 in accordance with an instruction from the administrator (S480). When the management office 28 manages a plurality of hydraulic work machines, switching of which hydraulic work machine data is displayed can be performed here.

  Subsequently, it is determined whether or not the warning transmitted in step S350 of FIG. 6 has been received (S490). If no warning has been received, the above processing is repeated. If a warning has been received, the fact that a warning has occurred in the large excavator 1 is displayed on the calculation display unit 29 to notify the administrator (S500). The administrator comprehensively judges the display and the display contents 2 and performs predetermined measures such as instructing to stop the operation of the large excavator 1.

FIG. 8 is a diagram showing an example of display content 2 displayed on the screen 29 a of the calculation display device 29.
In FIG. 8, the vertical axis represents the number of rotations, and the horizontal axis represents the date and time. A black circle indicates an average value D2 of the engine speed every 30 minutes. In this embodiment, an average value every 30 minutes is shown, but other time intervals such as every hour and every two hours may be used. When the latest average value D2 is recorded in step S470 of FIG. 7 and the data change processing of the display content 2 is performed, the display content 2 is also changed to display the latest average value D2. Further, the dotted line in FIG. 8 is the warning generation rotational speed N2 for determining the abnormality of the engine 13 used in step S340 of FIG. Further, when the average engine speed D2 falls below the warning generation speed N2, the engine monitor unit 21 on the excavator side determines that the engine 13 is abnormal and turns on the indicator 25 to warn the operator. At the same time, a warning signal is sent to the calculation display device 29 of the management office 28, and the calculation display device 29 displays the warning on the display screen in step S470 of FIG. The characters “engine abnormality occurred” in FIG. 8 are the warning display. Thereby, the administrator can know the fact that the engine abnormality has occurred and the change in the engine speed up to that, that is, the trend data, and can take appropriate measures against the engine abnormality.

FIG. 9 is a diagram showing an example of the display content 1 for determining the overhaul implementation time displayed on the screen 29a of the calculation display device 29.
In FIG. 9, the vertical axis represents the number of rotations, and the horizontal axis represents the date and time. A black circle indicates an average value D3 every 30 days. Although the average value every 30 days is shown in the present embodiment, it may be every other day such as every 10 days, every 20 days, every 60 days, or the like, or a configuration that can be switched to each other. When the latest average value D3 is recorded in step S450 of FIG. 7 and the data change processing of the display content 1 is performed, the display content 1 is also changed so that the latest average value D3 is displayed. Further, the dotted line in FIG. 9 indicates the warning rotation speed N1.

  Generally, in construction machines such as large hydraulic excavators, when the engine cylinder liner is worn, the engine output decreases, the engine load factor increases, and the thermal load increases, causing the cylinder liner to seize and damage the engine. There is. Therefore, it is necessary to overhaul the engine when the engine output decreases to some extent. Here, when the engine output decreases, the engine speed also decreases. Therefore, it is possible to estimate the decrease in engine output from the decrease in engine speed and predict the engine overhaul timing.

  The warning rotation speed N1 is provided as a reference value for determining the deterioration of the performance of the engine 13 based on the decrease in the engine rotation speed and predicting the overhaul execution time. The engine rotation speed is less than the warning rotation speed N1. In such a case, it is judged that overhaul is necessary. The warning rotation speed N1 is set to a higher rotation speed than the warning generation rotation speed N2 for determining an abnormality of the engine 13. As a result, the manager can analyze the downward trend from the trend data of the engine speed, predict the time when the engine speed falls below the warning speed N1, and determine the overhaul implementation time so as not to reach that time. .

  In the above, the process in step S120 in FIG. 3 constitutes a load input detecting means for detecting that a predetermined load has been applied to the engine, and the processes in steps S130 and S140 in FIG. When it is detected that a predetermined load is applied to the engine, the detection value of the engine speed detection means (engine speed sensor 23) is taken in based on the detection result, and is used as primary data of the engine speed. The first processing means is configured to store, and the processes of Step S150 and Step S160 in FIG. 3 and Steps S410 to S500 in FIG. 7 totalize the primary data of the engine speed, and calculate the second engine speed per predetermined time. Create the next data, and use this as trend data of engine speed related to preventive maintenance of the engine Constituting the second processing means for force.

  Further, the processing of step S150 of FIG. 3 and step S410 to step S450 of FIG. 7 creates the engine speed trend data related to the engine overhaul as the engine speed trend data related to the preventive maintenance of the engine. The processing in step S480 and the screen 29a of FIG. 7 constitute display means for displaying the trend data of the engine speed and the determination reference value of the engine overhaul implementation time.

  Further, the processing in steps S310 to S330 in FIG. 6 and steps S460 to S470 in FIG. 7 creates trend data of the engine speed related to the engine abnormality as trend data of the engine speed related to the preventive maintenance of the engine. 7, the process of step S480 in FIG. 7 and the screen 29a constitute display means for displaying the trend data of the engine speed and the determination reference value of the engine abnormality, and steps S340 to S350 in FIG. The processing in step S490 to step S500 in FIG. 7 and the screen 29a and the indicator 25 constitute alarm means for comparing the trend data of the engine speed with the determination reference value of the engine abnormality and outputting an alarm.

  In the present embodiment configured as described above, on the management office 28 side, the display content 1 of FIG. 9 is displayed on the screen 29a of the arithmetic display device 29 by the process of step S480 of FIG. The trend data related to the overhaul implementation time is displayed together with the criterion value. By using the display content 1, the administrator reads the change in the average value D3, which is the average value every 30 days, and analyzes the tendency of the engine rotational speed trend data to decrease. At this time, since the warning speed N1 is simultaneously displayed in the display content 1, the comparison can be easily performed, and the time when the engine speed falls below the warning speed N1 can be accurately predicted. As a result, the manager can accurately determine the overhaul implementation time, and preventive maintenance of the engine 13 can be accurately performed.

  Also, if an abnormality such as damage to the piston ring due to impact occurs in the engine 13 and the engine speed decreases, this is detected in step S160 in FIG. Knowing this, it is possible to take measures such as stopping the engine 13 as soon as possible, thereby preventing the engine from being damaged. Further, the management office 28 also displays the display content 2 of FIG. 8 on the screen 29a of the calculation display device 29 by the process of step S480 of FIG. 7, and displays the trend data of the engine speed and its abnormality warning. . As a result, the administrator can know the fact that the engine abnormality has occurred and the change in the engine speed up to that point, that is, trend data, and can take appropriate measures against the engine abnormality.

  As described above, according to the present embodiment, it is possible to accurately grasp the state of the engine 13 and to perform accurate preventive maintenance of the engine.

  In addition, it is possible to accurately predict the overhaul implementation time of the engine 13, and it is possible to prepare for overhaul in advance, and the influence of interruption of production work by the hydraulic excavator can be minimized.

  Furthermore, abnormalities in the engine 13 such as damage to the piston ring due to impact can be accurately predicted, and engine breakage can be prevented in advance.

  In the present embodiment, the description has been given by taking the large excavator 1 as an example. However, the construction machine engine management apparatus of the present invention may be implemented for other construction machines. For example, a wheel loader is used as the construction machine. A predetermined load may be used as a tilt operation of the lift arm.

It is a side view showing the whole structure of a large sized hydraulic excavator as an example of the construction machine used as the application object of the present invention. It is a figure showing the structure of one Embodiment of the engine management apparatus of the construction machine used as the application object of this invention with the hydraulic drive apparatus of a construction machine. It is a main flowchart of the process performed in the engine monitor part of the engine management apparatus of the construction machine used as the application object of this invention. As an example of a construction machine to which the present invention is applied, in a large excavator, a boom raising operation is input from the non-operating state to the operating lever device with the auto idle switch OFF and the throttle dial at maximum, and then returned to the non-operating state. It is a figure which shows the change of the actual rotation speed of an engine in the case of a failure. It is a flowchart which shows the overhaul data creation process of the engine management apparatus of the construction machine used as the application object of this invention. It is a flowchart which shows the abnormality detection process of the engine management apparatus of the construction machine used as the application object of this invention. It is a flowchart which shows the process of the calculation display apparatus installed in the management office of the engine management apparatus of the construction machine used as the application object of this invention. It is a figure which shows an example of the display content 2 displayed on the calculation display apparatus installed in the management office of the engine management apparatus of the construction machine used as the application object of this invention. It is a figure which shows an example of the display content 1 displayed on the calculation display apparatus installed in the management office of the engine management apparatus of the construction machine used as the application object of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Large excavator 6 Front work machine 7 Boom 10 Boom hydraulic cylinder 13 Engine 15 Main hydraulic pump (hydraulic pump)
19 Electric Lever Control Unit 20 Engine Control Unit 21 Engine Monitor Unit 23 Engine Revolution Sensor (Revolution Detection Unit)
25 Indicator 29 Calculation display device

Claims (8)

In an engine management device for a construction machine comprising an engine, a variable displacement hydraulic pump driven by the engine, and a hydraulic actuator driven by the discharge pressure oil from the hydraulic pump,
A rotational speed detection means for detecting the rotational speed of the engine;
A load application detecting means for detecting that a predetermined load is applied to the engine and outputting the detection result as a signal;
First processing means for taking in the detection value detected by the rotation speed detection means based on the detection signal of the load application detection means and storing it as primary data of the engine speed;
The primary data of the engine speed in the first processing means is totaled to generate secondary data of the engine speed per predetermined time, and this is output as trend data of the engine speed related to the preventive maintenance of the engine. And an engine management device for a construction machine. The engine management device for a construction machine according to claim 1,
The construction management engine management device according to claim 1, wherein the load application detecting means is means for detecting whether or not a predetermined work member driven by the hydraulic actuator has been operated. The engine management device for a construction machine according to claim 2,
The construction machine includes a front working machine having a boom,
The predetermined working member is the boom;
The construction machine engine management apparatus according to claim 1, wherein the load input detection means is means for detecting whether or not the boom is raised. The engine management device for a construction machine according to claim 1,
The engine management device for a construction machine, wherein the first processing means takes in an engine speed after a predetermined time has elapsed after the predetermined load is applied as a detection value of the speed detection means. The engine management device for a construction machine according to claim 1,
The engine management device for a construction machine, wherein the first processing means takes in the lowest engine speed after the predetermined load is applied as a detection value of the speed detection means. The engine management device for a construction machine according to claim 1,
The second processing means is means for creating trend data of engine speed related to the engine overhaul time as engine speed trend data related to preventive maintenance of the engine, trend data of the engine speed, and An engine management device for a construction machine, comprising display means for displaying a determination reference value of an engine overhaul implementation time. The engine management device for a construction machine according to claim 1,
The second processing means includes means for creating trend data of engine speed related to engine abnormality as trend data of engine speed related to preventive maintenance of the engine, trend data of engine speed, and engine An engine management apparatus for a construction machine, comprising display means for displaying an abnormality determination reference value. The engine management device for a construction machine according to claim 7,
The engine management apparatus for construction machinery, wherein the second processing means further includes warning means for comparing the trend data of the engine speed with the determination reference value of the abnormality of the engine and outputting an alarm.

Images